Palmitic acid inhibits the synthesis and secretion of thyroglobulin of rat thyroid follicular epithelial cell by downregulating thyrotropin receptor
10.3760/cma.j.cn311282-20221206-00674
- VernacularTitle:棕榈酸下调促甲状腺素受体减少大鼠甲状腺滤泡上皮细胞甲状腺球蛋白合成和分泌
- Author:
Youjuan FU
1
;
Hujun REN
;
Ling YUE
Author Information
1. 中国人民解放军中部战区总医院内分泌科，武汉 430070
- Keywords:
Lipotoxicity;
Thyrotropin receptor;
TSHR/cAMP signal
- From:
Chinese Journal of Endocrinology and Metabolism
2023;39(8):689-694
- CountryChina
- Language:Chinese
-
Abstract:
Objective:Exploring the role of thyrotropin receptor(TSHR) in lipotoxicity-induced thyroid function damage.Methods:Rat thyroid follicular epithelial cells(RTC) were stimulated with different doses of palmitic acid(PA), and the lipid content of the cells was observed through Oil Red O staining. The expression levels of TSH receptor(TSHR), Ttf1, and SSBP1 mRNA and protein in each group were detected using RT-PCR and Western blot. The TSHR protein level in the cell culture supernatant was measured using ELISA. Membrane TSHR was assessed through immunofluorescence and compared with the control group. We used PA to stimulate the TSHR over-expression(TSHR OE) and normal RTC, as PA+ TSHR OE group and PA group respectively, then testing Tg mRNA and protein, cAMP and Tg in cell supernatants levels, then comparing with the control.Results:RTC were stained into peau d′orange in PA groups. Compared with the control group, we found TTf1, SSBP1 and TSHR mRNA as well as protein levels in PA groups were decreased(all P<0.05), TSHR of the cell membrane and supernatants were reduced(all P<0.05), characterizing dose-dependent changes partly. Moreover, we found in PA group Tg mRNA level was downregulated( P<0.05), Tg protein levels were reduced in the supernatants and cells( P<0.05), cAMP level was decreased in cells( P<0.05); in TSHR OE group, Tg mRNA level was upregulated( P<0.05), Tg protein levels in cells and supernatants were increased(all P<0.05), cAMP level was similar. Compared with the PA group, we found in PA+ TSHR OE group Tg mRNA level was upregulated( P<0.05), Tg protein levels were increased in the supernatants and cells(all P<0.05), cAMP level was elevated in cells( P<0.05). Conclusion:PA induces lipid deposition in RTC, decreased synthesis and secretion of Tg. This effect is likely achieved through the downregulation of the TSHR/cAMP signaling pathway.
